Enhancing traits of agronomic and economic importance in wheat

小麦是加拿大最重要的经济作物之一。然而，它的生产不断受到各种因素的挑战，包括收获前发芽（PHS），即种子在收获前在母体植物上发芽，以及倒伏（倒性），即由于大风和大雨，作物通常在出穗后倒伏。这些因素加在一起导致粮食产量和质量显著下降，给小麦生产者造成巨大的经济损失。商品小麦生产中倒伏的发生率与氮肥使用量的增加有关，氮肥是获得更高产量所必需的。虽然化学生长调节剂可以控制作物高度并缓解倒伏问题，但由于其对生产者的额外成本以及相关的环境和食品安全问题，它们的使用是不可持续的。大多数商品小麦品种都是为了获得快速均匀的发芽和快速立苗而选择的，因此它们在收获前的潮湿条件下容易受到小PHS的影响。有利于小灵通的环境条件的严重程度和频率预计将随着气候变化而增加。因此，耐倒伏和小灵通的小麦品种受到加拿大小麦生产商的追捧。种子休眠和茎高/强度主要受植物激素调节；然而，小麦的潜在分子机制尚不清楚。小麦小灵通和倒伏耐受性在不同基因型间的差异也可归因于分别作为种子休眠和茎高/强度关键调控因子的遗传因子。然而，对小麦这些性状的遗传机制研究甚少。该研究旨在鉴定新的基因/等位基因，这些基因/等位基因可以作为基因组工具，促进小麦育种，增强对小PHS和倒伏的耐受性，从而提高产量和质量，并最大限度地提高加拿大小麦生产者的经济回报。

Wheat is one of the most economically important crops of Canada. However, its production is constantly challenged by a variety of factors including preharvest sprouting (PHS), which refers to germination of seeds on the parent plant prior to harvest, and lodging, which refers to falling over of the crop, often after ear emergence, due to high wind and rain. These factors in combination cause significant reduction in grain yield and quality, incurring high financial loss to wheat producers. The incidence of lodging in commercial wheat production is associated with increased usage of nitrogen fertilizers that is essential for attaining higher yields. Although chemical growth regulators can control crop height and mitigate the problem of lodging, their use is not sustainable due to its considerable additional cost to the producers and the associated environmental and food safety concerns. Most of the commercial wheat cultivars have been selected against seed dormancy to attain fast and uniform germination and rapid stand establishment, and as the result they are susceptible to PHS when wet conditions occur prior to harvest. The severity and frequency of environmental conditions that favor PHS are expected to increase with climate change. As a result, wheat cultivars with tolerance to lodging and PHS are sought by Canadian wheat producers. Seed dormancy and stem height/strength are regulated primarily by plant hormones; however, the underlying molecular mechanisms are poorly understood in wheat. Variation in PHS and lodging tolerance between wheat genotypes can also be attributed to genetic factors that act as key regulators of seed dormancy and stem height/strength, respectively. Nonetheless, the genetic mechanisms controlling these traits in wheat are scarcely studied. The proposed research is aimed at identifying novel genes/alleles that can be deployed as genomic tools to facilitate wheat breeding for enhanced tolerance to PHS and lodging, and thereby improve yield and quality and maximize economic returns to Canadian wheat producers.